Is a PET Scan the Right Option for You?

PET scans may be overused in lung, esophageal cancer survivors

(RxWiki News) For cancer survivors, vigilance is a key part of remaining cancer free. But new evidence suggests one cancer detection tool is being overused — and that isn’t helping anyone.

In a new study, researchers from the University of Michigan (UM) found that many hospitals may be inappropriately using positron emission tomography (PET) scans to look for returning lung and esophageal cancers. And this practice isn’t helping patients survive any longer.

Doctors use PET scans to diagnose disease in many areas of the body, including the heart, liver, bones, lungs, kidneys and thyroid, according to the Centers for Disease Control and Prevention (CDC).

When performing a PET scan, doctors have patients consume small amounts of radioactive isotopes. They then use a special camera to record, track and measure the isotopes inside the body. This lets doctors see cell activity inside the body, including fast-growing cancer cells. According to this study, many cancer patients receive PET scans as part of diagnosis, to see how advanced their cancer is and to see its response to treatment.

These scans aren’t recommended as the first option for long-term cancer monitoring, however. In fact, PET scans are one of the few imaging tools that Medicare sets limits on. Medicare currently allows three follow-up PET scans per patient, even when doctors order them after other scans.

Researchers from UM and Dartmouth-Hitchcock Medical Center teamed up to find out just how widely PET scans were being misused. They looked at Medicare data for more than 100,000 lung and esophageal cancer patients. All of these patients had cancer in the mid-2000s and follow-up care through 2011.

Researchers found that more than 22 percent of lung cancer patients and 31 percent of esophageal cancer patients received at least one PET scan during their follow-up period — without having a CT scan or any other imaging test first.

Some hospitals rarely used this approach. Others used PET scans as a first option. Some hospitals used PET scans eight times more frequently than others.

Regardless of whether patients went to a hospital where PET scans were frequently used or not, they survived about two years on average.

"PET scanning is a great technology and very effective, but using it in this way doesn't seem to make any difference for these cancers that have a relatively poor prognosis," said lead study author Mark Healy, MD, in a press release. Dr. Healy is a research fellow in the UM Department of Surgery.

He continued, "The appropriate use of PET scanning in follow-up care for lung and esophageal cancer is after findings on lower-cost imaging options."

While almost none of these patients reached the three-scan limit imposed by Medicare, Dr. Healy pointed out that even receiving one or two PET scans is extremely costly. He suggested that Medicare reevaluate how it structures its limits, and that radiologists and doctors coordinate better on how to care for recovering cancer patients.

This study was published Feb. 22 in the Journal of the National Cancer Institute.

It was funded in part by the National Institutes of Health, the Association for Healthcare Research and Quality and the American Cancer Society.

Study co-author Dr. Reddy received travel funding from the Cancer Treatment Centers of America and Novadaq Technologies Inc.

Review Date: 
February 22, 2016